Instructional dummy practice-keyboard apparatus



H. H. YELF INSTRUCTIONAL DUMMY PRACTICE KEYBOARD APPARATUS Filed March 15. 1923 Patented Oct. 2, 19 23.

uiarree starts Basemen s 0a Swansea; ENGLAND-- msrnuorroimr DUMMY'PRACTICEKEYBOARD APrAaA'r s.

' Application meamir ch s, 1923. Serial ms. 24 821.

Twall may concern:

Be. it that LHENRY HERBERT Yeats, a; subjlect of the li ingof Great Britmin and Ire and, anda resident of'Southsea, Hampshire, England, have invented a certain new and usef'ui Instructional Dummy Practice-Keyboard Apparatus, of Y which the following is a specification.

My invention relates to improvements in instructional dummy practice keyboards as applied to typewriters, adding and calcu lating machines, printers composing machines, and the like, and has for its object to provide a cheap, novel and simple means of reproducing approximately the action and tension of, for instance, an average standard typewriter keyboard for practice and instructional purposes.

My invention relates more particularly to the type of apparatus wherein a single dummy keyboard bearing characters is resiliently mounted in a frame so as to be capable of depression by pressure at any of the points, where characters are marked.

The present invention consists broadly of the employment of a single keyboard, con taining characters, which keyboard is not connected to the supporting frame butsupported merely b a central compression spring disposed thereunder, whereby when depressed at any point away from the centre a combined action of spring-yield and leverage is obtained. Further, by this means, the floating keyboard may be easily detachable for the purpose of interchanging the pattern at will, thus allowing for any range of difference in keyboard styles,

. and the ke board proper so mounted in its frame can e disposed in an outer combination box and copyholder, all as will be more fullv described hereinafter with reference to the accompanying drawings, wherein Figure 1 is a front elevation of one embodiment of the complete apparatus adapted for use in its application'to a typewriter.

F i ure 2 is a transverse section thereof on the hue 2-2, Figure 1.

Figure 3 is a perspective view of the keyboard component and its framework re moved from the box, the keyboard being partly broken away for clearness; and

Figure 4 is an enlarged section on the line 4-4, Figure 1, keyboard removed.

Referring to the embodiment illustrated by way of example in the accompanying drawings, a is a floating keyboard supdepression d in the base.

ported-on the framebase b by meauso'f a compression spring restin in a shallow T li'e frame, keyboard and containing box or casing (to be described) maybe constructed of wood, metal or any other suitable material; The base I) is rectangular, in the form shown,

and h'as side pieces, e, c, against-' -the faces .of which the side edges of the keyboard rest, andinwardly projectingribs, f, or

1 their equivalents such as stops, are provided to limit upward movement of the keyboard a. Corner flanges g, g, are secured to the front ends of the sides (1, e, to retain the keyboard in position.

The keyboard a. may be a flat plate like member as shown arranged in inclined fashion, and is furnished with an assembly of characters inscribed thereon, applied thereto, or fixedly for-med in the nature of buttons or equivalents h representative of the keys of a typewriter as for the example given. The keyboard a may he stepped or terraced, or the buttons themselves an ranged in a series of progressive steps. The strip z' is equivalent to the usual typewriter space-bar.

In operation, it will be seen that the keyboard is depressible at any spot, and as the centre spring c'acts as a fulcrum in every case of pressure at points displaced from the axial line of the spring, a combined leverage and spring-yield is the resultant action.

A separate dummy shift-key is independently mounted in a side piece e, and this is arranged to be resiliently depressed against the action of a leaf spring or the like is housed in a recess Z-see particularly Figure 4.

The practice apparatus so far described is carried in a box-like member m provided with a lid n and drop front 0. The lid n is furnished with supporting leg or flap p to maintain it in an inclined or upright posi tion as shown in Figures 1 and 2, the leg or flap p having a flexible or hinged connection 9 to the lid 01.. The interior of the lid n is constructed as a copy-holder, such for instance by means of the clips 1" whereby a pack of instruction cards or othercopy can thereon arranged in said casing, and a compression spring located beneath said keyboard and constituting the support therefor to produce the effect of key tension.

2. A practice keyboard device including a casing a keyboard plate loosely positioned in said casing and having key characters thereon, and a single centrally located compression spring arranged between the easing and the underside of the keyboard plate.

3. A practice keyboard device including a casing, a keyboard plate loosely positioned in said casing and having key characters thereon, a single centrally located con1pression spring arranged between the casing and the underside of the keyboard plate. and a spring supported shift key arranged in the casing at one side of the keyboard plate;

- 4. A practice keyboard device including a casing having inclined abutment members, a keyboard plate having thereon key characters,

and a compression spring arranged to normally maintain said keyboard plate against the inclined abutment members of the casin 5. i practice keyboard device including a box-like casing arovided with a hinged lid, a frame arranged Within the casing and in cluding side pieces abutment ribs carried by the side pieces, a central compression spring arranged within said frame, a keyboard plate resting on said spring and held by the same against the inner faces of said ribs, and corner flanges secured to the front ends of the side pieces.

In testimony whereof I have aftixed my signature hereto this first day of March, 1923.

HENRY HERBERT YELPY 

